Karen Carney column: Why Willian's experience is key for Chelsea
Former Chelsea and England midfielder Karen Carney, who retired after helping the Lionesses reach the World Cup semi-finals this summer, is writing columns for the BBC Sport website, working on Radio 5 Live and featuring on BBC TV this season.
When Chelsea play Ajax in the Champions League on Wednesday, Willian's experience will be key - you know what you're going to get and even if he is quiet, he can give you a bit of magic at any time.
Everyone knows his qualities and he's showed it year after year. It's no surprise that when he comes into the team, results improve. They have won five of the seven games he's started this season.
He's been one of Chelsea's best players for a few years, having played more than 300 games for them, but he was always overshadowed by another attacking player - Eden Hazard.
I've watched Willian in games in recent seasons and there would be times when he's running across the 18-yard box and you were thinking, 'why is he doing that?'. He was waiting to be fouled - there are so many free-kicks in key areas that he has won and either he or somebody else has scored from them. He does it on purpose.
And the difference with Willian is that a lot of players just pass, pass, and pass. He is a ball-carrier. It's sometimes the best way to get up the pitch because it takes the relief off the team.
One of the best things he does is slow the ball down when he's running at defenders. The art of that is it gives the opponent a respite but he is always in control of the ball. He then beats them with his skill.
Young players' enthusiasm, energy and drive is great but you always need a bit of experience. Those players, like Willian, who is 31 now and N'Golo Kante, who is a World Cup winner, are important when it comes to game management.
It's good to be raw but you need a mix
There's been a lot of praise for Chelsea's youngsters this season. The likes of Tammy Abraham, Mason Mount, Fikayo Tomori and Callum Hudson-Odoi have all done well but when results might not go so well, you need someone to say "it will take time".
You need that level-headedness when results are going well too - remind the young players not to get too high and to keep grafting. Experience matters.
When I was a young player at Birmingham City I would look up to the seniors all the time. Even afterwards, I wished I still had those players around for support. They see things that you have been through yourself. As an experienced player at Chelsea, I always tried to help the youngsters. Whether they wanted to listen was down to them!
But it's good to be raw. You need that mix of being fearless, experienced and guided. You will find it in every successful team.
At the moment, expectations are not massive at Chelsea because they accept this year is a transitional period. The fans seem excited about it but next year, they will want a bit of progression in terms of picking up silverware.
Now they have a legend as the manager in Frank Lampard and there is a good group of coaching staff who have been there a while. They are bringing the younger players through and are using the academy after picking up that transfer ban.
Chelsea previously spent a lot of money looking for a number nine in Gonzalo Higuain and Alvaro Morata but they had a kid who came through the ranks and went out on loan to Swansea and Aston Villa - Abraham, who is now 22, and has come back in and proven his point.
Lampard is a positive influence on special Mount
I've been impressed with Mount the most.
I watched him play at Solihull Moors against Birmingham a while ago and he scored a hat-trick. I heard a lot about him at Chelsea and he would train with the under-21s on the other side of the hedge behind us.
He went abroad with Dutch club Vitesse Arnhem and I think that really helped. People think of him as a young player but he has had two seasons of first-team football and picked up a lot of minutes for a 20-year-old.
To go abroad when he did at 18 was a challenge and then he went to the Championship with Derby - also under Lampard - and came forward again. He has a lot of ability and has proven he can be trusted.
He knows what it's like to be a winner too. He won youth titles with Chelsea's academy and has had success with England Under-19s. He's a special player who just needs to keep improving. Under Lampard, there's a positive influence on him because the manager was his hero, Chelsea's record goalscorer and was an attacking midfielder, like Mount.
It will be interesting to see what happens in the Champions League on Wednesday because while Chelsea's young players have done well this season, Ajax have been a model club for youth success for years. How they do things is incredible.
I read that they take young players to the front of a house and ask if they can get in. The player would say the door was locked so they would say "try around the back". They couldn't get in around the back so "try going over". That's how you play football - if you can't go through the middle you have to go around the sides or over the top.
Their methods have been light years ahead and they have used that as a conveyor-belt for their youth.
But the Champions League is a cup competition so Chelsea shouldn't fear anyone they come up against. In Europe, anything can happen.
Karen Carney was speaking to BBC Sport's Emma Sanders.